Pen nib



FIG. 1 is a perspective view of a pen nib;

FIG. 2 is a front view of a pen nib;

FIG. 3 is a rear view of a pen nib;

FIG. 4 is a left side elevation of a pen nib;

FIG. 5 is a top plan view of a pen nib; and,

FIG. 6 is a bottom view of a pen nib. 

CLAIM The ornamental design for a pen nib, as shown and described. 